The Ultegra Di2 derailleurs are a bit more bulbous. Photo: Caley Fretz

The larger size is even more noticeable on the front derailleur. Photo: Caley Fretz

The demo bikes at the World Center of Cycling at the UCI in Aigle, Switzerland. The frames were re-badged Giants.

The new cables and connectors are smaller, and completely water proof.

The Ultegra Di2 has the same battery design as the Dura-Ace version. Photo: Caley Fretz

Hold down the button for two seconds to activate the rear derailleur adjustment mode. Keep holding it to check battery life. Photo: Caley Fretz

Shift front chainrings mid-sprint, mid-mountain? Sure, why not.

Tech writers forget the 80 percent rule outside Aigle, Switzerland.

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Shift front chainrings mid-sprint, mid-mountain? Sure, why not.

AIGLE, Switzerland (VN) — At nearly half the cost of its elder sibling, the supposedly second-tier Ultegra Di2 group is set to bring push-button electronic shifting to a much wider audience. Manufacturers are pricing Ultegra Di2-equipped bikes around $4,000 and up — not exactly cheap, but nowhere near the $8,000-$12,000 commonly asked for Dura-Ace Di2 models. And the new, cheaper option may actually be even better than its bank robber of an elder brother.

So when Shimano requested our presence in Aigle, Switzerland, home of the UCI, to give the group a good run through, we couldn’t refuse. Plus the riding in Switzerland isn’t half bad.

The specs

Total weight for the full group, including non-electric bits like the cranks and brakes, is 2,482g. That’s 80g more than mechanical Ultegra, 263g more than Dura-Ace Di2, 333g more than mechanical Dura-Ace, and 127g lighter than mechanical 105. Price is on par with Dura-Ace mechanical, around $2,500.

Everything is a bit bigger and less sleek. Both derailleurs have chunkier sections that house the motor.

The cables have changed, from a four internal wires to two. This decreased their diameter, and the diameter of the connectors. The cables and connectors are also now completely waterproof, without the sleeves needed for Dura-Ace Di2. Two wiring harnesses are available, one for internal routing and one for external, both in multiple lengths. Dura-Ace Di2 and Ultegra Di2 are not compatible due to the different harnesses, though Dura-Ace Di2 should be getting the new harness type soon if the folks at Shimano are smart, and word is they are.

The new smaller battery used on Dura-Ace Di2 is retained for Ultegra Di2.

The hoods are now a bit thinner, more like the old 7800 shape but not as tall and with a flatter top.

Testing
Now, the good part. We wondered whether the massive drop in price would equate to an equivalent drop in quality.

With a few decent rides in the Swiss Alps and plenty of time tinkering with the stuff, I am confident in saying that, in fact, Ultegra Di2 is better than Dura-Ace Di2. That’s right, better. For half the price. Not all that surprising really, since we are talking electronics here and just like my four-year-old iPhone, the latest generation does quite a bit more for less money. But the new group is impressive and exciting, nonetheless.

Despite what Shimano representatives say, the rear shifting on their Di2 systems — both of them — is a bit slower than mechanical options from all three major brands. That’s largely because you can’t dump gears with one swing of a lever: you need to tap the button for each shift. This is why I still race on SRAM Red: the rear shifting is tighter and crisper than Di2. I can upshift three gears at once, and I can pull the shift paddle into the bars for mid-sprint shifts. I also like the hood shape more. But all of that is just personal preference; I would be perfectly happy on a Di2 group as well.

Shifts with Di2 are always spot on, though, something that can’t be said for even the best mechanical systems. Sometimes, in a state of fatigue, you just don’t swing that little paddle quite far enough.

The front shifting with Di2 is undeniably the best available. Having ridden SRAM Red, Campagnolo Super Record 11, both Di2 systems, and Dura-Ace mechanical in the last few months, the Di2 comes out as the clear winner. The ability to shift from little ring to big ring while stamping out 500 watts is unrivaled. That performance is a function of the motorized derailleur itself, which can be built much stiffer than any mechanical derailleur. It’s also why I think SRAM had better jump on the electronic bandwagon sooner rather than later: now that more riders will have access to Di2, that front shift quality will soon become the norm.

Caley Fretz

Associate Editor Caley Fretz can be found chasing races along the backroads of Europe or testing bikes and gear in the mountains outside Boulder, Colorado. If you can't find him there, check the coffee shop across from VN World Headquarters.